For those interested in getting their 007 MK1 a step or two closer in detail to the 009 without sacrificing the 007 tonality, I recommend trying Sylania or GE Fat Bottle 6CA7 NOS tubes. They have the biggest soundstage of all the EL34's and are the brightest and most detailed of all the EL34's I have tried by a good margin. They are for certain the "least warm" of all the EL34's I have tried and the most dynamic. They really bring out the best in the BHSE 007 combination.
As an aside- they are the worst tubes for the 009 which need that thickness element.